U.S. Pat. Nos. 5,899,348, 6,039,195 and 6,327,770 disclose closure and container packages that are particularly well-suited for prescription applications. The container includes a sidewall with an externally threaded finish and a deflectable release element cantilevered from the finish on a side of the threads remote from the open mouth of the container. The closure includes a base wall with an internally threaded peripheral skirt having locking lugs at the edge of the skirt remote from the base wall. These locking lugs on the skirt cooperate with a locking lug on the deflectable release element of the container to secure the closure to the container in a child-resistant mode of operation. To release the closure, the release element is deflected downwardly toward the container sidewall to move the locking lug on the release element out of engagement with the locking lug on the closure skirt. A dome extends from the inner periphery of the base wall and has an external thread that is adapted to be received within the open mouth of the container in an inverted non-child-resistant mode of operation of the closure. A general object to the present invention is to provide a closure and package of the general type disclosed in the noted patents, in which the closure is convertible between child-resistant and non-child-resistant modes of operation without inverting the closure with respect to the container finish.
A closure having child-resistant and non-child-resistant modes of operation, in accordance with a first aspect of a presently preferred embodiment of the invention, includes a plastic inner shell having an upper end, a skirt with at least one internal thread, at least one external bead on the skirt and at least one external engagement element on the skirt. A plastic outer shell has a skirt externally encircling the skirt of the inner shell. The outer shell has at least one internal bead on its skirt, at least one internal first engagement element on a side of the internal bead adjacent to the upper end of the inner shell, at least one second engagement element on a side of the internal bead remote from the upper end of the inner shell, and at least one third engagement element adjacent to an edge of the skirt remote from the upper end of the inner shell. The inner shell is positionable within the outer shell at a non-child-resistant first position with the external bead on the inner shell disposed on a side of the internal bead on the outer shell remote from the base wall of the inner shell, and with the second engagement element on the outer shell disposed for engagement with the external engagement element on the inner shell. The inner shell is positionable within the outer shell at a child-resistant second position with the external bead on the inner shell disposed on a side of the internal bead of the outer shell proximate to the base wall of the inner shell, and with the external engagement element of the inner shell disposed for engagement with the internal first engagement element of the outer shell.
In the preferred embodiment in accordance with this first aspect of the invention, the internal bead on the outer shell is disposed between circumferentially continuous internal channels on the skirt of the outer shell, the first internal engagement element on the outer shell includes a circumferential array of teeth within a first of the channels, and the second internal engagement element on the outer shell includes a circumferential array of teeth within a second of the internal channels. The external engagement element on the inner shell in the preferred embodiment of the invention includes a circumferential array of teeth on the external bead, which are engageable with the teeth in the first and second internal channels of the outer shell in the child-resistant and non-child-resistant modes of operation respectively.
A closure in accordance with a second aspect of the present invention includes a plastic inner shell having a skirt with at least one internal thread, and a plastic outer shell having a skirt externally encircling the skirt of the inner shell and at least one engagement element adjacent to an edge of the skirt. The skirts of the inner and outer shells have opposed radially facing surfaces. One of these surfaces has a bead with at least one tooth. The other of the surfaces has a bead, with at least one first tooth disposed above the bead and at least one second tooth disposed below the bead. The inner shell is positionable within the outer shell in a first mode of operation such that the bead on the one surface is positioned below the bead on the other surface, and the at least tooth on the bead of the first surfaces is disposed to engage the at least one second tooth on the other surface. The inner shell is positionable within the outer shell in a second mode of operation such that the bead on the one surface is positioned above the bead on the other surface, and the at least one tooth on the bead of the first surface is disposed to engage the at least one first tooth on the other surface. In the preferred embodiment of the invention, the at least one tooth on the bead includes a circumferential array of teeth on the bead, the at least one first tooth includes a circumferential array of first teeth, and the at least one second tooth includes a circumferential array of second teeth. In the preferred embodiment, the bead with the circumferential array of teeth is an external bead on the inner shell, and the bead with spaced circumferential arrays of first and second teeth are an internal bead and internal arrays of teeth on the skirt of the outer shell.